Compilare: main.cpp: In function 'int main()': main.cpp:51:26: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen(input,"r",stdin); ^ main.cpp:52:28: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen(output,"w",stdout); ^ main.cpp:54:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%ld%ld",&n,&m); ^ main.cpp:58:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%ld%ld",&x,&y); ^ main.cpp:75:9: warning: 'poz' may be used uninitialized in this function [-Wmaybe-uninitialized] bf(poz); ^